Two types of elevator entrance assemblies that are commonly used to provide access to elevators are swing entrance assemblies and sliding entrance assemblies. Swing entrance doors open by pivoting about a hinge when the door handle is pulled. Sliding entrance doors open by traveling along a linear track in tandem with an elevator cab door. This invention relates to an improved sliding door assembly, especially in constructing new buildings.
An elevator door entrance assembly refers to the frame and sliding door which separates a hallway (corridor) from the elevator shaft (hoist way or shaftway). As the door on the elevator cab opens, or closes, it drives the entrance door open or closed. In the past, the construction of a sliding door for elevators has been relatively labor intensive, time-consuming, expensive and has presented significant safety hazards.
A traditional problem associated with the installation of new elevator systems in new buildings is that the entrance door installation has been almost the last step in the overall system installation procedure. This results in a long period during construction wherein there is an unfinished gap between the hallway and the elevator shaftways. If tools, loose bolts, etc. should fall down the elevator shaft, they may injure those below. This unfinished gap is typically covered with a temporary barrier such as plywood or wooden barricades. Frequently during the course of construction, these barriers are removed and not replaced, or replaced carelessly.
In addition, the door, and possibly parts of the frame and other components of the entry assembly have been generally lifted and installed from the elevator platform or temporary work platform after sufficient work has been performed by the elevator constructors and electrical power put in-place to allow the platform to move in the shaftway. This sequence is a result of the entrance design and installation method which requires that the frame be installed and aligned prior to hanging the door. This procedure requires that the elevator platform (work platform) be lifted and lowered in the elevator shaft as a requirement of entrance assembly installation. This procedure makes the moving elevator platform and elevator shaft unavailable for other work. For example, if it requires one-half of a day to install the frame, door, etc. of each entrance assembly of an elevator shaft and the building is 20 floors high, the moving platform must be used for 10 work days for installation of entrance assemblies on that shaftway. Often the moving platform must be operated by a special, and costly, operator and is required for other construction tasks, which must wait until the moving platform is no longer needed for the installation of entrance door assemblies.